Yemen's rival parties are making military preparations and threatening to return to war as hunger and cholera are increasing in the Arab world's poorest nation, U.N. officials said Thursday.

U.N. special representative Hans Grundberg told the Security Council that despite serious efforts to shield Yemen, it has been drawn into the Israel-Hamas war in Gaza, with Houthi rebels continuing to attack ships in the Red Sea and the United States and United Kingdom responding with strikes on military targets in Houthi-controlled areas.